Keratins are a class of structural proteins widely represented in biological structures, especially in epithelial tissues of higher vertebrates. Keratins may be divided into two major classes, the soft keratins (occurring in skin and a few other tissues) and the hard keratins, forming the material of nails, claws, hair, horn, feathers and scales.
The toughness and insolubility of hard keratins, which allow them to perform a fundamental structural role in many biological systems, are also desirable characteristics in many of the industrial and consumer materials currently derived from synthetic polymers. In addition to possessing excellent physical properties, keratin, as a protein, is a material with a high degree of chemical functionality and, consequently, exhibits many properties that synthetic materials cannot achieve. Keratin is, therefore, well suited to the development of products with high-value, niche-market applications. Keratin is also an environmentally acceptable polymer produced from a sustainable resource and therefore has environmental benefits over synthetic materials. Following the global trend of developing materials from renewable sources produced in a sustainable process, a range of materials has been produced from keratin, most commonly in the form of keratin films.
At the core of a new industry producing biopolymer materials from keratin it is essential to have a process for extracting keratin from its source that is economically viable, sustainable from an environmental perspective, and produces a stable and versatile product. Methods used to date for the extraction of keratin that maintain the integrity of the individual proteins have been designed for the purpose of protein analysis and characterisation and consequently are not viable on an industrial scale, from an economic and environmental viewpoint. Methods used to date for the economic dissolution of keratin have significantly degrading effects on the protein, and consequently the dissolved protein retains few of the physicochemical properties that lead to the desirability of keratin as a biopolymer, such as the ability to reconstitute into tough materials.
It is an object of the invention to go some way in overcoming the disadvantages with known processes or at least provide the public with a useful choice.
In at least one embodiment the invention strives to provide an economic and environmentally acceptable process for the dissolution of keratin proteins that maintains the structural integrity and chemical functionality of the proteins during the dissolution process and leads to a stable and versatile keratin derivative product for the development of biopolymer materials.